The police identified the suspect as Zhu Shibin from Harbin, the provincial capital. He was caught in Daqing City of the same province.

The motive of the crime is not yet known, the police said.

The 34-year-old used black powder disassembled from firecrackers to make the bomb, and set it up Sunday morning at a Dicos restaurant in Anda of Suihua City, Heilongjiang, the police said.

Zhu made an anonymous phone call to the restaurant's delivery hotline, claiming that there would be an explosion at the restaurant within five minutes, the police said, adding that he blackmailed the restaurant for 100,000 yuan (16,000 U.S. dollars).

The police rushed to evacuate people, during which the explosion occurred at 9:34 a.m. on Sunday. The blast injured two policemen, who are still in hospital.